If your Hydro Flask smells bad or contains what appears to be mold what should you do and how should you clean it?
If you’re like me then every now and then you’ll leave your Hydro Flask with the good intention of cleaning out tomorrow only to leave it for a couple of weeks with the lid on.
When it comes time to use your hydro flask you open it only to find an incredibly bad smell coming out at you and possibly some visible signs of mold.
Mold is harmful to your health and can easily grow in your Hydro Flask if left unchecked. In this article we’ll discuss exactly how to clean mold from your Hydro Flask, both the bottle and the lid.
Can Hydro Flasks Get Mold and Bad Smells? If So, How?
Hydro Flask definitely have the potential to grow mould or to obtain bad smells if you don’t clean them properly.
Mold likes to grow in dark damp places and given that your Hydro Flask is used for wet drinks and can remain wet for long periods of time this can create perfect growing conditions for mold.
Just leaving water in your Hydro Flask for a couple of days is unlikely to create a bad smell. However, leaving drinks like coffee or smoothies or anything with milk in it in your Hydro Flask can quickly turn disgusting.
What Happens If You Drink From a Moldy Hydro Flask?
There are many different types of mold, some are good (like those used in blue cheese) and some are really bad for you.
Generally mold growing in a drink bottle is NOT considered to be healthy and may actually be harmful to your health.
The below video talks a little bit about what happens to you if you drink mold and what the risks are.
Below is another video from a chiropractor who had a patient that was getting a lot of infections and having a lot of difficulties and they found out that this may have been caused from them not cleaning the lid of their cup properly.
See under the lid of Yeti’s as well as Hydro Flasks is a rubber gasket. You actually need to take this out to clean it and stop mold build up but not many people do.
Check out the video where he talks about this mold situation below:
How To Get Rid of Bad Smells From Your Hydro Flask
Okay, so let’s say you just have a bad smelling Hydro Flask and it’s not actually moldy.
Maybe you left a drink in there for a couple of days maybe it’s just started to smell over time.
How do you easily get rid of bad smells from your Hydro Flask? There are a few ways you can do this:
Wash it well
The first, and most obvious, thing to do is to wash your Hydro Flask well if you haven’t already.
Fill up your sink with warm soapy water and brush it thoroughly with a bottle brush.
Once clean rinse out your Hydro Flask and leave it to air dry or dry with a towel and then leave it to air for a bit.
This does a good job of removing minor smells from the bottle.
Soak it in vinegar
Another technique is to get a small amount of white vinegar and pour it into your Hydro Flask bottle.
Put on the lid and then shake your bottle so the vinegar covers the entire inside of the bottle.
Then leave this to sit for 15 to 30 minutes before washing out, rinsing your bottle and then leaving to dry and air out.
Bottle bright tablets (from Amazon)
If you’re lazy, like me, then bottle bright tablets are super easy to use and give your bottle a good clean and should remove bad smells as well as built up residue.
All you have to do is put the tablet in your bottle, fill it up with water and then let it do it’s thing.
It will bubble and fizz and get rid of all the bad smells as well as stains in your Hydro Flask.
This article by the kitchn states that:
The main ingredients are hydrogen peroxide, baking soda, citric acid, and salt, plus a few other plant-based agents like cellulose.
You can pick up these easy cleaning tablets at Amazon for a pretty cheap price and get them shipped to your door.
Get some bottle bright tablets for cheap at Amazon
Sacrificial Water
For minor smells I found it helpful to fill up my Hydro Flask with water (ideally boiling water) and then leave to sit for a few hours to soak up any smells.
I then tip out the water into the sink or onto the garden and then repeat the process.
I find that the water tends to absorb the odors and overtime my bottle stop smelling musty.
Dry Rice and Detergent/Vinegar
If you think the bad smell is coming from some built-up residue on the inner walls of your Hydro Flask then this technique can work wonders.
Inside your bottle can be difficult to clean as sometimes a bottle brush won’t quite reach every spot or scrub it hard enough.
Put a handful of dry rice in your Hydro Flask as well as a bit of detergent or vinegar and some water.
Put the lid on your Hydro Flask and shake vigorously for 2 to 5 minutes.
The dry rice will act as an abrasive and will rub off any residue and the detergent or vinegar should help to remove the stench.
How To Get Rid of Mold From Your Hydro Flask
If you found mold growing in your Hydro Flask bottle then you’ll need to do an extensive clean of it to make sure you remove all of the mold.
Here is exactly step-by-step how to get rid of mould from your hydro flask.
Step 1: Rinse Well
Before you begin washing your bottle make sure you rinse it well with water getting out any leftover drink that is in there.
I like to partially fill up my bottle with water put the lid on and shake it and then pour the water out and rinse again.
Step 2: Add a Bit of Vinegar and Shake (Then Leave For 30 Minutes)
Now add a bit of vinegar into your Hydro Flask and put the lid back on and shake the bottle to ensure that the vinegar covers all of the inside of the bottle.
Now leave the vinegar to do its magic for approximately 30 minutes.
If you don’t have vinegar click here to get some directly from Amazon
Step 3: Make a Baking Soda Paste
Take some baking soda and put it into a bowl and add a bit of water and mix it in in order to create a paste.
If you don’t have baking soda it’s super cheap
Get some cheap baking soda directly from Amazon
Step 4: Use Paste + Bottle Brush To Brush Away Mold
Apply the baking soda paste to your bottle brush and then use your bottle brush to clean the inside of your Hydro Flask.
Take care to scrub well and make sure you get the entire inside surface with the brush.
You will notice some fizzing from the baking soda reacting to the vinegar. This is normal and helpful in the cleaning process.
If you have a small mouth Hydro Flask and can’t reach everywhere in there you can either use a toothbrush to reach the hard to get areas or simply put some baking soda in your hydro flask and shake it well. You can also use the dry rice method mentioned above.
Step 5: Leave To Sit For 15 Minutes
Now that you’ve cleaned your bottle with baking soda leave it to sit for a further 15 minutes.
Step 6: Rinse With Boiling Water
Once done rinse your bottle well. I like to start by using boiling water as this will help to clean the mold and disinfect your bottle.
You can also just use room temperature water or warm water if you prefer.
Step 7: Scrub Again
Scrub again with a now clean bottle brush just to help remove any remaining baking soda or vinegar as you don’t want to be drinking that.
Step 8: Rinse Well
Now rinse your bottle extremely well and leave to dry and air out.
How To Clean Mold From Your Hydro Flask Lid
Often people fail to clean the lids of their Hydro Flask properly and this is one of the main places where hidden mold can get in because of the rubber gasket as other moving parts that can hold moisture and be hard to clean.
Step 1: Fill Up Bowl With Vinegar
Get a small bowl and partially fill it up with vinegar.
Step 2: Remove Rubber Gasket and Soak Gasket and Lid Parts in Vinegar for 30 Minutes
All Hydro Flask bottle lids have a rubber gasket on the inside. Use a knife or other tool to remove the rubber gasket.
For straw lids remove the straw and pop off the swivel mouth piece from the main part of the lid.
Place all lid parts in the bowl of vinegar and let soak for half an hour.
Step 3: Scrub Well With Baking Soda Paste
Just like the bottle above use the baking soda paste you have made and scrub all lid parts well with a brush or with a cloth, making sure to get into all the nooks and crevices.
Step 4: Leave To Sit For 15 Minutes
Once brushed put it back in the vinegar bowl to soak for another 15 minutes.
Step 5: Rinse With Boiling Water
Tip out the vinegar and then rinse all lid components well with boiling water. This helps to wash away the baking soda and vinegar as well as any leftover mold.
The boiling water also helps to kill germs and sterilise your lid.
Step 6: Scrub Again
Scrub the pieces again with a clean brush to remove any leftover cleaning products/chemicals as you don’t want to be drinking these.
Step 7: Rinse Well
Give everything a really good rinse under your tap with either warm or cold water.
Step 8: Leave Out To Air Dry
Leave the lid pull apart and let all the different parts air dry.
Step 9: Reassemble Lid and Put Back on Bottle
Once everything is completely dry reassemble all the pieces of the lid together making sure to put the rubber gasket firmly into place.
You can now put your lid back on your Hydro Flask and start using it again.
What NOT To Do With a Smelly or Moldy Hydro Flask
There are a few things you should NOT do with a moldy Hydro Flask
Put It In The Dishwasher
Hydro Flask clearly state both on their website and in their product packaging not to put your Hydro Flask in the dishwasher. Doing this can cause damage to the vacuum sealed insulation and it can also cause discoloration to the outside paint.
Some lids like the straw lid and flip cap CAN be put in the dishwasher, but if they are moldy it is better to clean them using the method mentioned up above.
Read more about whether or not you can put your Hydro Flask in the dishwasher
Don’t Soak It In Water
Hydro Flask also tell you NOT to soak your Hydro Flask in warm soapy water as this can cause the outside paint to become discolored.
If you wish to soak your bottle then fill up the interior with warm soapy water while keeping the exterior dry.
Don’t Clean With Abrasives or Steel Wool
In my article on how to clean your Hydro Flask properly every time I talked about not using hard abrasive cleaners or steel wool on your Hydro Flask.
These can scratch the paint off the exterior of your bottle and they can also scratch the inside (which isn’t as big of a deal).
Using super fine 0000 steel wool or a magic eraser on the inside can polish the stainless steel well and help to remove hard stains.
Get some 0000 Steel Wool at Amazon
How To Avoid Getting a Smelly + Moldy Hydro Flask in Future
Ideally you want to avoid your Hydro Flask getting smelly and moldy in the first place and this can be easily done by cleaning and drying your Hydro Flask well on a regular basis.
It doesn’t take long to clean a Hydro Flask and if you take good care of it then it should last you a lifetime.